Punch press



G. H. KUHL PUNCH PRESS June 26, 1956 6 Sheets-Sheet 1 Filed July 21,1955 June 26, 1956 G. H. KUHL 2,751,984

PUNCH PRESS Filed July 21, 1955 6 Sheets-Sheet 2 '2 jg /0Z 60f6 Z4 w G.H. KUHL June 26, 1956 PUNCH PRESS Filed July 21, 1955 6 Sheets-Sheet 3 QNN eor ge ifjflfid J 1 7w, wk

June 26, 1956 Filed July 21, 1955 G. H. KUHL PUNCH PRESS fi JJ 5 J a/ 35i a 45 6 Sheets-Sheet 4 G. H. KUHL PUNCH PRESS June 26, 1956 6Sheets-Sheet 5 Filed July 21, 1955 G. H. KUHL PUNCH PRESS June 26, 19566 Sheets-Sheet 6 QQ MN Mi Mi m%\ 3 mQ k5 Filed July 21, l

PUNCH PRESS George H. Kuhl, Glen Ellyn, Ill.

Original application February 27, 1951, Serial No. 212,975. Divided andthis application July 21, 1955, Serial No. 523,447

Claims. (Cl. 164-90) This invention relates to a punch press.

This application is a division of my co-pending application filedFebruary 27, 1951, as Serial Number 212,975.

It is the general object of this invention to produce a new and improvedpunch press.

Another object of the invention is to produce a dual punch press whichincludes a ram carrying two male die parts and mounted for reciprocationin a horizontal plane, and two female die parts each cooperable with oneof the male die parts so that two punching operations can beaccomplished in each stroke of the press.

It is a more specific object of the invention to produce a dual punchpress of the type described in the preceding paragraph which includesmeans for accurately adjusting each male die part relative to the otherparts of the press in order to secure perfect alignment of the dies.

It is a further object of this invention to produce in a singleapparatus a self-feeding punch press which may operate not only on onebut two die sets simultaneously, each die producing either a similar ora dissimilar part and capable of operating at higher rates of speed andproductivity by reason of improved distribution and proportion of movingand stationary masses of the press.

It is another object of the invention to produce a selffeeding punchpress which puts to use the return stroke of the ram and thus toincrease the productivity of punch presses without a correspondingincrease in cost or size.

Other and further objects of the invention will be apparent from thefollowing description and drawings, in which:

Fig. l is a side elevation of a dual punch press embodying theinvention;

Fig. 2 is an end view of the upper portion of Fig. 1;

Fig. 3 is a top plan view of the apparatus shown in Fig. 1;

Fig. 4 is a vertical section along line 44 of Fig. 3;

Fig. 5 is a side elevation of the upper portion of Fig. 1 showing theopposite side of the press;

Fig. 6 is a vertical section along line 66 of Fig. 5;

Fig. 7 is a vertical section along line 77 of Fig. 3; and

Fig. 8 is a horizontal section along line 8-8 of Fig. 7.

While this invention is susceptible of embodiment in many difierentforms, there is shown in the drawings and will herein be described indetail one specific embodiment, with the understanding that the presentdisclosure is to be considered as an exemplification of the principlesof the invention and is not intended to limit the invention to theembodiment illustrated. The scope of the invention will be pointed outin the appended claims.

For the purpose of exemplary disclosure the feed means of this inventionis shown as used in conjunction with a dual punch press. As s'hownin thedrawings the press includes a frame A supporting the press B, drivemeans C for driving the press and the feed means D for feeding the workpiece to the press.

The frame A includes rigid legs 10 adapted to support the apparatus, thelegs preferably being angle irons welded -nitecl States Patent 0 orotherwisesecured together to provide a sturdy'mounting. The press B issupported on the top of the frame and includes a pair of bolster plates20 and 21 secured to the frame A at spaced positions and upstandingvertically therefrom in parallel relationship to each other. Extendingbetween and secured to each of the bolster plates are four tie rods 2225which provide the mounting means for the movable ram of the press. Theends of the tie rods are securely fastened to the bolster plates by thebolts shown. Four bearings 26-29 are provided for carrying the rams,each of the bearings being slidably mounted upon a different one of therods.

It will be noted that the press reciprocates horizontally. This fact,together with the low center of gravity of the apparatus, increases thestability of the press and permits high speed operation.

As best shown in Figs. 4 and 5, the bearings are integrally secured toan annular collar member 30 forming a part of theram and which isprovided with an internal recess 31. Secured in the recess as by thescrew devices 32 is an externally threaded annular sleeve 33 whichextends both ways from the recess 31 and parallel with the tie rods. Thesleeve 33 is provided with an integral flange extending radiallyoutwardly therefrom and provided with an internal channel 34 located inthe recess 31 and receives the screw devices 32 previously described.

As previously stated, the particular embodiment of the invention chosenfor illustration is shown as used with a dual punch press, that is apunch press which has similar parts on each side and is adapted toperform a punching operation upon each half stroke as it isreciprocated. Thus the parts of the press to the left and to the rightof the recess 31 (as seen in Fig. 4) are similar. In order to avoidunnecessary repetitions only the die part on one side of the recess 31will be described in detail, it being understood that the descriptionapplies to the die parts on the other side of the flange to whichsimilar reference numerals carrying the letter a have been given.

A punch holder 40 is provided with an annular restricted portion 41received within the sleeve 33 and with an outwardly extending annularportion 42 provided with external threads 43 which lie in the same planeas the threads 35 of the sleeve. The sleeves 43, however, are turnedoppositely to the threads 35, for example the threads 43 may beright-hand threads while the threads 35 may be left-hand threads. Acollar member 45 is provided with internal threads which engage both ofthe threads 43 and 35 so that rotation of the collar member 45 serves tomove the punch holder 40 inwardly and outwardly with respect to thesleeve 33. The outer face 46 of the punch holder 40 is concave in shapeand preferably is shaped as a section of a sphere. Coincid-ing with theconcave face 46 is a convexly spherical shaped member 47 secured to themale die plate 48.

A centrally located lug 49 is secured to the die plate 48 and receivedin a recess 50 in the punch holder 40. As will be noted from thedrawings, the recess 50 is larger than the lug 49 so that the die plate48 may be shifted slightly accurately to position it parallel to thebolster plates. This adjustment may be utilized to con-- pensate formanufacturing inaccuracies and its provision minimizes precisionoperations in the building of the press which would otherwise benecessary if the adjustment were not provided as it is necessary thatthe surfaces of the ram be perfectly parallel to the bolster plates. Theloose fit between the lug and recess permits such alignment and aplurality of screws 51 are provided in the punch holder 40 and to clampthe male die part of the ram in properly aligned position. Preferablythree such screws 51 are provided equally spaced about the boss. Securedto the die plate 45 is a die carrying plate 52 which carries the maledies 53 and 54.

The particular press illustrated has been set up to along in the samemanner as the plugs.

carry male dies for forming'washers from a continuous strip of material.Thus the die 53 serves to cut a circular hole in the material while thedie 54 makes a second circular cut having a larger diameter than thefirst cut to form the annular washer. Scrap material is cut from thestrip by cutter blades 55 and 55a each fixed to the bottom of each ofthe male die parts'and adapted to cut the strip against a recess formedin the opposing face of the female part of the die.

A pair of studs '56 and 56a is fixed each of the bolster plates andextend toward the ram parallel to the tie rods. 'A pair of sleeves 57and 57a is fixed to each of the male die parts and slide on the studs inorder to serve as guides for the ram during its reciprocation. It willbe noted that the studs and sleeves 56 and 57 are in vertical alignmentalong one side of the male die part 45 while the studs and sleeves 56aand 57a are in vertical alignment along theopposite side of the male diepart 13a. Q

To the right of the male die plate is a female die plate 60 providedwith suitable openings 61 and 62 matching the male die parts. The femaledie plate 611 is sup ported against spacer plates 63 and 64, the latterbeing secured to the bolster plate 2%. Each of the spacer plates isprovided with holes extending therethrough matching the holes 61 and 62to provide the elongated passages shown which open into an annularrecess 65 provided in the bolster plate. a

Between the male and female die parts there is provided a stripper plate66 also provided with openings matching the openings 51 and 62 andspaced from the female plate to define a passage 67 through which thestrip of material constituting the work piece is fed.

As the die is reciprocated and the work piece is fed into positions inline with the dies, the first die 53 cuts a circular opening in thestrip each time the die is reciprocated. The circular plugs which arecut out by the die 53 stack up in the passage 61 and are movedtherealong as the work progresses and finally drop into the annularrecess 65. Similarly, the male die. part 54 completes the cuttingoperation to form the washer; the washers stacking up in the openings 52and moving there- It is preferred that the male die part be providedwith a projecting boss :13 properly to align the work piece with thecutting edges of that die in order to insure ,that the washers beaccurately formed.

A pair of chutes 7t) and 79a communicate with the recesses 65 and 65arespectively to guide the washers as they fall from the recesses into apair of containers 71 and 71a located at the bottom portion of the frame(Fl l). I prefer to provide two such containers inasmuch as the dieparts on either side of the ram may not be similar in nature; thus forexample one die part may be cutting washers having a 1 inch diameter andthe other washers having a 1%. inch diameter. The

provision of two containers, one communicating with each of the recessesin the bolsters permits the segregation at the machine of differentlyformed parts. If desired, a

separate chute may connect with the opening 61 to separate ma pings fromthe washers.

Scrap material from the press continues its downward movement in thepassage 67 until it strikes an inclined plate '72 supported on brackets73 and 74 secured to the frame, which plate directs the scrap materialinto a container pan (not shown) which may be placed in the lower partof the frame.

The drive means C include a motor 815 connected by means of a V beltSite a rotatably mounted pulley 82.

A pair of V belts 8S connect the pulley with a rotatably mountedfiywheelS4. The flywheel carries a crank 85 on either side thereof to each ofwhich is secured a pitman $6. The two pitmans so provided are-eachconnected to opposite sides of the die,'that is to the annular collar 30which is carried by the slides.

The flywheel 84 is fixed toa rotatably mounted shaft 87 supported atboth ends in the frame and to which is fixed a gear 88 meshing with asecond gear 89. The ratio of the mass of the flywheel to the mass of themale die carrying parts is high to provide sufiicient inertia for thepress to perform a punching operation on each stroke. Also the high massratio contributes to the stability of the press. The gear 89 is fixed toa shaft 90 which carries at its outer end (Fig. 3) a pair of meshingbevel gears 91 one of which is secured to a drive shaft 92. The driveshaft )2 serves to operate the feed means D which in turn serves toadvance the work piece intermittently to the die as the latter isreciprocated.

Inasmuch as the press illustrated in the drawings is a dual press twofeed means are provided, one for each press. Hills the feed means aresimilarly constructed (and similar parts will be given similar referencenumerals with the letter :1 added) each may be adjusted individually soas to feed at different rates. Thus if the press is performing twodistinct operations, one on each die, feed means may be individuallyadjusted to feed the work piece at the proper rate in order toaccommodatethe operations of each press. a

When used with a dual press, the work piece which is in the formofstrips of material 101 and a, is fed from an overhead source which maybe large rolls over which the material is passed. As the strips enterthe press each is passed over a guide roller 101 rotatably mounted in afitting 102 secured to the top of the feed means. A friction device 103is provided to produce the proper tension on the work piece, thefriction device including a shoe 104 fixed to the fitting 102 and asecond shoe 1% slidably mounted on bolts 196 and urged against the firstshoe by means of a spring 107. The'degree of friction may, of course, beadjusted by adjusting the screws 106. V V

Adjustably secured to thetop of the bolsters 20 and 21 is a mountingframe for the feed means including two spaced upright parallel platesand 111 secured at their bottoms to base plates 112 and 113. Secured toand extending horizontally between the base plates is V a first clampingplate 114.. A second clamping plate is vertically spaced beneath thefirst clamping plate and secured thereto by means of bolts 116. A pairof spaced parallel horizontal shafts 117 and 118 are secured to thebolster plate and serve as the mounting means for the feed mechanism. Aswill be noted from an inspection of Figs. 4 and 6, the base plates 112and 113 are positioned above the shafts 117, 118 while the clampingplate 115 is positioned beneath the shafts. Each of the base plates andthe clamping plates is provided with substantially herni-cylirrdricalgrooves more accurately to fit the outer surfaces of the shafts 117 and118 and thus the entire mounting means may he slid along the shafts 117and 118 and clamped thereto at any desired point. Thus adjustment can bemade for various thicknesses of the work piece and for various workingstrokes of the press. Furthermore, the adjustment of the feed unitsmakes it possible to align the entrance of the strip into the feed meansexactly opposite the exit-of the strip therefrom and perfectly alignedwith the dies of the press to enable a large variety of die sets to beused. in the press. Referring now to Figs. 7 and 8,, it will be notedthat the side plate 110.is provided with a rectangular cut-out portion120 in which there is slidably mounted a block 121 which rotatablycarries one end of a shaft 122 on which there is fixed a feed roller123. A similarly con-' structed block is slidably mounted in the plate111 and carries the other end of shaft '122. Fixed adjacent theright-hand end (as'seen in thosefigures) of the plates. 11%} and 111 isa second rotatably mounted shaft 125 to which 'is fixed a second feedroller 1'26. The roller 126 is, as clearly shown in the drawing, mounted.in parallel to the roller 123 and forms therewith a nip 127 throughwhich the work strip 190 may be led.

Each of the feed rollers 123 and 126 is driven fiom the drive means ofthe machine. As best seen in Figs. 3 and 6, the drive shaft 92 isprovided with two pairs of bevel gears 135) and 130a, one of whichcarries a sprocket 131 over which a chain 132 is passed. The chainengages a second sprocket 133 secured to one end of the shaft 125 fordriving the same. Intermediate sprockets 134 and 135 are provided totake up the slack as the feed means may be adjusted inwardly andoutwardly as previously described. Mounted on the shaft 125 adjacent thefeed roll 126 is a spur gear 140 which meshes with a second spur gear141 fixed on the shaft 122. Thus as the press is operated both of thefeed rolls are positively driven.

It will be clear from the foregoing description that if the two feedrolls are pressed together to close the nip between them the strip ofmaterial 100 would be constantly fed to the press. This, of course, isnot the object to be achieved in the particular type of press showninasmuch as the press requires that the material be fed intermittently,that is, be advanced as the die parts are moved away from each other topresent a fresh portion of the strip and held stationary as the dieparts are brought together to perform their punching operation. Meansare provided for alternately opening and closing the nip between therolls, so that when the nip is closed the material is firmly grasped bythe rolls and fed downwardly to the press. As the nip is opened bothrolls lose their frictional grasp of the material and hence thefrictional device holds the strip stationary against advancement untilthe nip is again closed.

To effect the alternate opening and closing of the nip,

the shaft 122 rotatably carries a cam 149 which cam may be fixed theretoby a plurality of set screws 150. The shaft is rotated in synchronismwith operation of the press by the drive means C. A cam follower 151rides upon the cam and is mounted in a lever arm 152 which is fixed to ashaft 153 rotatably mounted in the plates 110, 111, by a split clampformed in the end of the lever arm through which clamp a lock screw 154extends. As best shown in Fig. 8, the shaft 153 extends through therectangular cut-out portion 120 in the side plate 119 and is providedwith a flattened portion 155 located in a cut-out portion 156 of theblock 121 and bearing against a flat face 157 thereof. A compressionspring 153 has one end located in a recessed portion 159 at the end ofthe plate 116 while its other end bears against the adjacent face of theslidable block 121 to urge the block constantly in a direction closingthe nip between the feed rolls. The force with which the spring biasesthe nip toward closed position may be adjusted in the usual manner bymeans of the screw device 160. The previously described adjustment ofthe lever arm relative to the shaft 153 afforded by the split clamp andlock screw 154 is provided to take advantage of the most rapid rise ofthe edge of the flattened surface 155 against the face 157 whenever achange is made from one thickness of stock to another.

from the foregoing it can be seen that as the shaft 153 isintermittently oscillated one edge of the flattened portion 155 thereofis brought against the face 157 of the block to shift the blocklaterally against the spring. inasmuch as the feed roller 123 is mountedin the block, such shifting movement of the block serves to open the nipbetween the rolls.

It will be noted that the cam follower 151 is mounted on the end of abolt 162 which is threadable on the free end of the lever arm 152. Alock nut 163 is provided to lock the cam follower at any position towhich it may be moved by adjustment of the bolt 162. By so adjusting thecam follower it is clear that the period of dwell of the rolls in theopen nip or closed nip position may be regulated. Inasmuch as the stripis fed toward the die parts only when the nip is closed such adjustmentpermits regulation of the amount of material fed during each cycle ofthe die. Thus if the nip remains closed for a greater proportion of thecycle a longer length of material is fed than otherwise.

The timing of the opening and closing of the nip may be adjustedrelative to the reciprocation of the die parts rotating the cam upon itsshaft. By loosening the set screws 15%) the cam may be rotated in eitherdirection relative to its shaft and fixed in any desired position. Thusthere is provided a simple means of timing the feed of the work striprelative to the closing of the die parts. If the operator finds that thestrip is in motion at the time the die parts are closed the press may bestopped and the cam 14-9 adjusted so as to open the nips slightly soonerin the cycle of the die. Again if the length of the strip to be fedduring each cycle of the die is great the cam can be adjusted on itsshaft so as to feed the strip during substantially the entire cycle, thenip opening just prior or simultaneously with the contact of the maledie part therewith.

In the particular embodiment of the feed means chosen for illustratingthe invention, manual means are provided for opening the nip between thefeed rolls at any time in the cycle of the press, which means serves tomaintain the nip open until manually closed. To this end a shaft 179 isrotatably mounted in the plate 111 (Figs. 6 and 7) to which is secured ahandle 171 for rotating the shaft. The inner end of the shaft carries aneccentric pin 172 which bears against the bottom face of the lever arm152. Rotation of the handle in a clockwise direction (as viewed in Fig.7) serves to lift the lever arm and hence to open the nip between therolls. The nip will remain open until the direction of rotation of thehandle is reversed permitting the cam 149 to resume control of the nipposition.

I claim:

1. A punch press comprising a base, a pair of spaced parallel bolsterplates vertically upstanding from the base, a plurality of parallel tierods extending horizontally between and secured to the bolster plates, abearing mounted on each tie rod, a flywheel mounted on a shaft rotatablysupported at each end in the base, pitmans connecting the flywheel tothe bearings for reciprocating the same in a horizontal plane withrotation of the flywheel, a ram secured to the bearings, an annularsleeve integrally secured to the ram and having external threads at oneend thereof, a punch holder having external threads turned opposite tothe threads on the sleeve, a ring engaging the threads on the punchholder and sleeve and rotatable to shift the punch holder relative tothe sleeve, said punch holder being provided with a concave outer facehaving a central opening therein, a male die part having a convex facecoinciding with the concave face of the punch holder and a central lughaving a loose fit in said opening, means for securing the lug in theopening to secure the male die part in adjusted position on the punchholder, a female die part cooperable with the male die part and carriedon the base, and means for rotating the flywheel.

2. A punch press comprising a base, a pair of spaced parallel bolsterplates vertically upstanding from the base, a plurality of parallel tierods extending horizontally between and secured to the bolster plate, abearing mounted on each tie rod, a flywheel mounted on a shaft rotatablysupported at each end in the base, pitmans connecting the flywheel tothe bearings for reciprocating the same in a horizontal plane withrotation of the flywheel, a ram secured to the bearings, an annularsleeve integrally secured to the ram and having external threads at oneend thereof, a punch holder having external threads turned opposite tothe threads on the sleeve, a ring engaging the threads on the punchholder and sleeve and rotatable to shift the bOSs relative to thesleeve, said punch 7 holder being presided with a concave outer facehaving a; central opening therein, a male die part having a convex facecoinciding with the concave face of the punch holder and a central lughaving a loose fit in said opening, means for secaring the lug in theopening to secure the male die part in adjusted position on the punchholder, 21 female die part cooperable with the male die part and carriedon the base, a plurality of plates spacing the female die part from theframe, each of said plates havinga hole aligned with the female diepart, a chute carried by the base and connected to said holes wherebymaterial punched by the male die part is fed into said chute, and, meanscarried by the base for rotating the flywheel.

3. A punch press comprising a base, a pair of spaced parallel bolsterplates vertically upstanding from the base, a plurality o'f parallel tierods extending horizontally between and secured to the bolster plates, abearing mounted on each tie rod, a flywheel mounted on a shaft rotatablysupported at each end in the base, pitmans connecting the flywheel tothe bearings for'reciprocating the same in a horizontal plane withrotation of the flywheel, a ram secured to the bearings, an annularsleeve integrally secured to the ram and having external threads at oneend thereof, a punch holder'having external threads turned opposite tothe threads on the sleeve, a ring engaging the threads on the punchholder and sleeve and rotatable to shift the punch holder relative tothe sleeve, said punch -l'iC-l-L6I being provided with a concave outerface having a central opening therein, a male die part having a convexface coinciding with the concave face of the punch holder and a centrallug having a loose fit in said opening, means for securing the lug inthe opening to secure the male die part in adjusted position on thepunch holder, 21 female die part cooperable with the male die part andcarried on the base, a plurality of plates spacing the female die partfrom the frame, each of said plates having a hole aligned with thefemale die part, a recess in the outer face of one of the bolster platescommunicating with said hole, means on the base for supporting acontainer, a chute opening at one end to said recess and at the otherend to the container whereby material punched by the male die part isfed into said chute, and means carried by the base for rotating theflywheel.

4. A dual punch press comprising a base, a pair of spaced parallelbolster plates vertically upstanding from the base, a plurality ofparallel tie rods extending hori- V zontally between and secured to thebolster plates, a caring mounted on each tie rod, a flywheel mounted ona shaft rotatably supported at each end in the base, pitmans connectingthe flywheel to the bearings for reciprd eating the same in a horizotalplane with rotation of the flywheel, a ram secured to the bearings, anannular sleeve integrally secured to the ram and having external threadsat each end thereof, a punch holder at each end of the sleeve, eachpunch holder having external threads turned opposite to the threads onthe adjacent ends of the sleeve, a ring engaging the threads on onepunch holder and on the adjacent end of the sleeve and rotatable toshift the punch holder toward and away from the sleeve, a second ringengaging the threads on the other punch holder and the threads of thesleeve adjacent thereto, said second sleeve being rotatable to move thelast mentioned'punch holder toward and away from the sleeve, each ofsaid punch holders being provided with a spherically concave outer facehaving a central opening therein, a pair of male die parts each having aconvex face coinciding with the concave face of one of the punch holdersand a central lug adapted to have a loose fit in each of said openingswhereby each male die part may be shifted relative to a punch holder,means for securing each male die part ed on each tie rod, meansforreciprocating the bearings on the tie rods, .a ram secured to thebearings, an annular sleeve integrally secured to the ram and havingexternal threads atone end thereof, a punch holder having externalthreads turned opposite to the threads on the sleeve, a ring engagingthe threads on the boss and sleeve and rotatable to shift the punchholder relative to the sleeve,

said punch holder beingprovided with a concave outer face having acentral opening therein, a male die part having a convex face coincidingwith the concave face of the punch holder and a central lug having aloose fit in said opening, means for securing the lug in the opening tosecure the male die part in adjusted position on the punch holder, and afemale die part cooperable with the male die part and carried on thebase.

References Cited in the file of this patent UNITED STATES PATENTS467,908 Altman Feb. 2, 1892 1,697,817 Kuhn Jan, 1, 1929 2,148,855 CannonFeb. 28, 1939, 2,453,875 7 Terhune Nov. 16, 1948

